IFFALCON U85X vs TCL A400 PRO

iFFALCON U85 handles HDR in a rather dual manner – on one hand, it can surprise with a solid peak brightness of around 650 nits, which places it well above average in this price segment. This is particularly evident in full-screen, bright scenes. Examples from movies like Life of Pi or the final test sequences from The Meg prove that the TV can maintain the strength and essence of the HDR effect when the entire panel has to "light up," delivering truly satisfying experiences. However, problems begin in high-contrast scenes, where smaller, bright details appear on the screen; the dimming algorithms prioritize deep blacks to such an extent that they can suppress the brightness of small highlights to just 100 nits, drastically reducing the dynamism of the image and depriving us of the true "punch" we expect from HDR standards. However, the question of colors remains a sweetener; thanks to the use of the PFS phosphor filter (marketed as QLED by the manufacturer), they look very good, achieving nearly 94% coverage of the DCI-P3 color palette, allowing for a rich and vibrant image in most content.

The TCL A400 Pro is a moderately bright TV. Its peak brightness reaches about 600 nits. That level already allows for a real HDR effect and in many movies it does produce a noticeably more attractive picture than SDR. However, it is not a level that overwhelms by brightness alone. The A400 Pro is not one of those TVs that "attack" the viewer with a powerful flash in every dramatic scene. The biggest limitation is visible with small bright elements on a dark background. Due to rather aggressive control of the dimming zones, the TV can significantly reduce their brightness — in extreme cases down to around 100 nits. That means small lights, sparks, stars, or single highlights can be much less visible than they should be. That said, this is not done without reason. The A400 Pro does this to keep blacks as deep as possible and to limit haloing around bright objects. It's a deliberate compromise: the TV more often chooses deeper blacks over maximally bright, point-like highlights. On one hand this is understandable, especially with a limited number of dimming zones, but on the other hand you should be aware that the HDR effect will not always be as strong as the peak brightness alone would suggest.

On the plus side, the colors are worth noting. The PFS LED filter used here, marketed by the manufacturer as QLED, produces suitably saturated colors. Our measurements showed about 94% coverage of the DCI-P3 gamut and about 74% of BT.2020, which is a solid result for this class.

We tested the factory colors in the iFFALCON U85X model in “Film” mode, which is definitely the most reliable among all available settings, although it is still far from perfect. The main problem that stands out in both SDR and HDR content is improper white balance - an excess of blue and red components gives the image a slight purple tint, which undermines the naturalness of film scenes. However, an even greater challenge is the way the television manages its brightness. Analyzing the gamma curve for the SDR signal, we noticed significant instability: instead of sticking to the reference value of 2.4, the device oscillates around 2.2, only to suddenly experience an unnatural jump to around 3.0. In practice, this leads to confusing effects - large bright areas on the screen appear too dark, while smaller elements are unnecessarily brightened. A similar feature can be found in the EOTF curve, which makes the image unpredictable and loses its cinematic authenticity.

As standard, we carried out color measurements in the best-calibrated mode, Filmmaker Mode, the one that is supposed to be closest to the creators’ intent. The A400 Pro, of course, also offers other picture modes, but in practice they suffer from much larger color errors and alter the image character more strongly. We won’t go into those modes in detail in this part of the test. So how does the factory color reproduction perform? In short: really very well. In fact, looking at our measurement results, it’s excellent. Both the white balance and the luminance response were set surprisingly precisely. The errors were so small that during testing we genuinely rubbed our eyes in disbelief. Such good out-of-the-box settings don’t happen often, even in TVs operating in Filmmaker Mode. All the more reason to praise TCL, because the A400 Pro right out of the box can produce an image very close to how the source material should look. The results were so good that you could easily think someone had already paid extra attention to that unit and tried to calibrate it.

Our nitpicking really comes down to just one thing. In SDR content the image was slightly brighter than the reference for a dark room, because the factory gamma was set closer to 2.3 than to 2.4. It’s not a big error and most viewers probably won’t even notice it.

However, it should be noted that we’re talking about our specific review sample. With factory colors there can always be some variation between units, production batches, or screen sizes. So we don’t assume that every A400 Pro will look identical straight out of the box.

After professional calibration of the movie mode, we must admit that the effect is more than satisfactory – the iFFALCON U85X undergoes a true transformation. Color errors in SDR content dropped to a level below 2, making them practically imperceptible to the human eye. We managed to set the white balance almost perfectly, and brightness management (gamma) became nearly exemplary. As a result, with standard quality materials, the television looks simply perfect, and it's hard to find any faults with it.

In the case of HDR signal, the situation has also improved significantly, although here the nature of the device is a bit more pronounced. Color errors have been reduced to around 3, which is an outstanding result in this price range. However, it is worth taking a look at the EOTF chart (available on the right side of the screen in the filters: 4K HDR, gamma / EOTF) to see what is not immediately visible regarding brightness management by the U85. Although the reference line looks decent, in actual film scenes, the television still interprets the signal "in its own way" due to very aggressive local dimming algorithms. Does this disqualify this model for watching HDR content? Absolutely not. It's simply a typical ailment of almost every Mini-LED that has to reconcile high brightness with an attempt to maintain deep black. One just has to be aware of these technical limitations, which are unavoidable in this segment.

Despite its excellent factory tuning, we couldn't resist checking how the TCL A400 Pro would respond to a professional calibration. Since the starting point was so good, we were even more curious whether we could squeeze even more out of this TV. And here we have to boast: we managed to bring our unit to absurdly low color errors. Results below 1 are something you don't see every day, even on very good TVs. Such results are more often associated with professional reference monitors than with a lifestyle TV for the living room. In terms of white balance and color reproduction, the A400 Pro after calibration simply performed outstandingly. The only thing we can pick at after a deeper analysis concerns the brightness behavior. The TV can manipulate luminance levels depending on the content being displayed, and quite often the image is a bit darker than it should be according to the standard. This most likely stems from the way the Mini-LED backlight and local dimming algorithms work in this model. However, that doesn't spoil the overall impression, because in terms of color precision alone the A400 Pro after calibration reached a level we really didn't expect.

When it comes to scaling the image to 4K resolution, the iFFALCON U85X performs solidly. The device efficiently enhances low-quality signals, making even older materials look clean and clear on the 4K matrix. At extremely low resolutions, such as 480p, you can notice slightly jagged edges (especially on thin lines), but let's face it – this is a scenario you'll only encounter when watching very old footage, so it's not a real issue in everyday use.

However, the digital processing aimed at smoothing tonal transitions is significantly worse. Although the menu features a function called “Gradual Smoothing”, its effectiveness is at least debatable. In practice, it does not effectively reduce banding (color stepping), and worse, it can cause more harm than good. This filter can be too aggressive where it shouldn't be, artificially smoothing out details that should not be touched, such as the natural texture of the face or fine details of the skin's texture. Instead of improving quality, this feature can give the image an unnatural, “plastic” look, so it's best to use it with great caution or, better yet: leave it turned off.

Digital video processing is unfortunately one of the weaker points of the TCL A400 Pro. That doesn't mean the TV performs badly, but it's hard to call it anything clearly above standard. The upscaling itself is adequate: edges are smoothed fairly well, the image doesn't look overly sharp or pixelated, and lower-quality content can be watched without major discomfort. At the same time the overall look is slightly soft and it lacks the precision that the best image processors in more expensive TVs can deliver.

Much worse, however, is its handling of tonal transitions caused by heavy compression. TCL equipped the A400 Pro with a "Gradual Smoothing" feature that in theory should reduce visible color banding and artifacts in lower-quality content. In practice its effectiveness is very limited. It does not improve tonal transitions in any noticeable way, and at higher settings it can also smooth out image details, giving the picture an artificial, slightly blurred character. For that reason we think it's best to leave this feature off. The A400 Pro handles basic image scaling decently, but if you often watch heavily compressed content with visible posterization, this model won't be one of the best choices.

In contrast to budget constructions, which in dynamic sports scenes may resemble a slideshow, the iFFALCON U85X is a heavyweight contender equipped with a panel featuring a native refresh rate of 144Hz. However, it is worth remembering that in the world of movies, series, or sports, we will mostly operate at 120Hz due to the specifics of image enhancement systems. Such a fast panel is excellent news for gamers and sports fans, as it opens the door to advanced motion settings that simply don't exist in cheaper 60-Hz models.

We manage everything from the "Motion Clarity" menu, where instead of using pre-set, often too aggressive modes, we definitely recommend a custom configuration based on two sliders. The most important of them, reduction of flicker, is responsible for smoothness in films – here, it's best to aim for a value around 4, which will maintain a natural, cinematic character of motion without falling into the artificial "soap opera effect." On the other hand, the first slider, reduction of blur, is the key to success in sports broadcasts. In this case, it's worth going all out and setting it to maximum, ensuring that the image during fast actions on the field remains sharp, and annoying trailing is eliminated.

The TCL A400 Pro is equipped with a 144 Hz panel, but in practice we're most interested in how it performs at 120 Hz. That's the refresh rate used by most consoles today, as well as many sports broadcasts and high-frame-rate content. In this range the TV performs quite well. Motion clarity is really good, especially after properly configuring the motion smoothing. The "Motion Clarity" feature improves smoothness. Its settings include two sliders that let you tailor the motion smoothing to your preferences — separately for lower- and higher-frame-rate material. That way you can achieve either a more cinematic look or a noticeably smoother picture. If you don't want to tweak settings manually, you can use presets such as low, medium, high, cinema, or nature.

iFFALCON U85X is an exceptional device for gamers that has virtually everything you can expect from a modern screen for consoles or PCs. Here we find two fully-fledged HDMI 2.1 ports with full bandwidth of 48 Gbps, which opens the door to key technologies such as VRR and ALLM, ensuring smooth gameplay without tearing and with minimal latency. The TV handles high refresh rates at various resolutions without any problem, and a real curiosity is the mode that allows for up to 240Hz when dropping to Full HD quality. The entire system is managed by the Game Bar (a faithful copy from TCL), which allows for instant switching of picture modes, customization of the interface appearance, or even adding a virtual crosshair in the middle of the screen.

When it comes to features for gamers, the TCL A400 Pro performs excellently. The TV has practically everything you can expect from a gaming TV today: 4K support at high refresh rates, VRR, ALLM, correct implementation of HDR formats in games, including Dolby Vision, and HGiG. Because of that it works well with both next-gen consoles and PCs. Another plus is the inclusion of a Game Bar, a special panel with the most important settings for gamers. From it you can quickly check basic signal information, refresh rate, and active features, and also adjust the look and behavior of some settings to your own preferences. This is a solution that may not change picture quality by itself, but it greatly improves the convenience of using the TV while gaming.

The only thing to complain about is the number of full HDMI 2.1 ports. The A400 Pro has only two such ports out of four, and one of them also functions as eARC. In practice this means that if someone wants to connect two next-gen consoles and a soundbar, they may hit some limitations. In that scenario you'll have to either swap devices or use extra equipment, for example an AV receiver or a soundbar with HDMI inputs. Despite this, it's hard not to rate the A400 Pro very highly as a gaming TV. The gaming feature set here is really powerful.